Should I build a PC with single channel RAM or duel channel RAM?

[yesman]

I'm planning on building a PC for DCS simulations specifically and I'm not sure if it will be more beneficial to have a single-channel or a dual-channel memory config.

I've seen a thread that says that a single channel should be better than dual channel but that thread was written in 2019 and since this DCS has moved to multithreading I've read in another place that multithreading uses dual channels more efficiently.

Should I build a system in a single channel RAM or duel channel RAM?

[Rudel_chw]

In real world terms, the performance difference is pretty insignificant … here is a well made comparison:

 

https://gamersnexus.net/guides/1349-ram-how-dual-channel-works-vs-single-channel?showall=1

 

When I build a PC I always prefer to get a single dimm of the largest capacity I can get, so as to easily double the system ram in a future upgrade, as using 4 Dimm is almost always not good for performance.

[diego999]

There's no difference if you're not looking at a benchmark, and even then, it's almost nothing.

I bought my PC with a single stick, then added another for dual channel. Now I'm using all 4. I tested, measured and ran benchmarks. The difference was pretty much just noise.

Using all 4 can limit you in case you're overclocking RAM or aggresively trying to reduce timings. In that case you might run into problems. In normal use scenarios it doesn't matter.

[BitMaster]

I disagree totally for many reasons.

Maybe the most non-technical is that everybody seeks for the best performance and there you throw it away.

When a system needs that much RAM like DCS I highly doubt, tho I cannot proof it, that going from 128bit to 64bit bus width won't hinder performance.

The thing about DDR MHz is about bandwidth, you can settle with 2133 if you doubt that dual-channel, quad- hexa- octa- channel systems give any benefit.

 

Guys, I cannot believe you throw away 64bit's of bandwidth.. left in disbelief...I need a beer. 

 

[LucShep]

1 hour ago, BitMaster said:

I disagree totally for many reasons.

Maybe the most non-technical is that everybody seeks for the best performance and there you throw it away.

When a system needs that much RAM like DCS I highly doubt, tho I cannot proof it, that going from 128bit to 64bit bus width won't hinder performance.

The thing about DDR MHz is about bandwidth, you can settle with 2133 if you doubt that dual-channel, quad- hexa- octa- channel systems give any benefit.

 

Guys, I cannot believe you throw away 64bit's of bandwidth.. left in disbelief...I need a beer. 

 

I agree with @BitMaster.

Even though DDR5 is better in this regard than DDR4 was before, it is clear that the rule still persists - two sticks of RAM are always better than just one.
The main advantage is higher memory bandwidth, higher access efficiency, and lower latency. It's all better with two sticks (instead of just one).

DDR5 is much cheaper than before, there is no reason to not get a Dual kit (say, 2x 32GB or 2x 48GB) that is meant to be installed and run in that configuration.
All these Intel and AMD processor based systems that we go for are designed to run ideally in Dual-Channel memory configuration. 
Especially if you're already spending on a system, not doing it is counter intuitive. It's neglecting a particular part of the system performance that most people here crave for. 

There are plenty articles and videos explaining this in a more cientific aproach (and with tests).
This one for example is a bit old (dates from when DDR5 was out and too expensive, and DDR4 mobos for 12th gen were a better compromise) but have a listen from 3:19 and on:

 

Edited November 18, 2023 by LucShep

[Rudel_chw]

49 minutes ago, BitMaster said:

Guys, I cannot believe you throw away 64bit's of bandwidth.. left in disbelief...I need a beer. 

it would matter more if the memory bandwidth was a limiting factor on the PC, but actually it matters little … that’s why real-world benchmarks show little difference.

[BitMaster]

But if I pull out 1 channel I am left with 32GB only

Seriously, I could accept it as a compromise but not a recommendation. There are 5-10% to gain in most of the test in the vid you posted, some where tie and only 1 was 2% slower ..and that was DDR3 back in 2014 with 3-4GB tested. We are talking 30-50GB in use with DCS these days, tendency going even higher.

If there is 5-10% on the table not only a few would do a lot and even pay some cash to get them 5-10%. 

I would like a to see 4k or 8k video render, that should show some bigger difference. The more memory is needed the wider the gap.

 

edit:

if you aim for 64GB minumum for DCS, there ain't no single 64GB desktop DIMM yet, you have to go dual channel. Only if you were to go 32GB, which is regarded as not enough for many scenarios, you could get away with 1 channel.  LoL

Edited November 18, 2023 by BitMaster

[Rudel_chw]

37 minutes ago, BitMaster said:

Seriously, I could accept it as a compromise but not a recommendation.

 

ok, I will abstain from recommending it, as I dont feel like debating this point.